The Institute for Telecommunication Sciences (ITS) has developed an objective video quality assessment system that emulates human perception. The perception-based system was developed and tested for a broad range of scenes and video technologies. The 36 test scenes contained widely varying amounts of spatial and temporal information. The 27 impairments included digital video compression systems operating at line rates from 56 kbits/sec to 45 Mbits/sec with controlled error rates, NTSC encode/decode cycles, VHS and S-VHS record/play cycles, and VHF transmission. Subjective viewer ratings of the video quality were gathered in the ITS subjective viewing laboratory that conforms to CCIR Recommendation 500-3. Objective measures of video quality were extracted from the digitally sampled video. These objective measurements are designed to quantify the spatial and temporal distortions perceived by the viewer. This paper presents the following: a detailed description of several of the best ITS objective measurements, a perception-based model that predicts subjective ratings from these objective measurements, and a demonstration of the correlation between the model's predictions and viewer panel ratings.